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August 4, 2010
This circuit features automatic Exit and Entry delays and a timed Bell Cut-off. It has provision for both normally-closed and normally-open contacts, and a 24-hour Personal Attack/Tamper zone. By using the Expansion Modules, you can... [more]
August 4, 2010
When this alarm is activated its Siren will sound once - for up to 20-minutes. Then it will switch off and remain off. The basic circuit has a single zone with independently adjustable Exit and... [more]
August 4, 2010
This is a simple SCR based burglar alarm circuit. Its features include automatic Exit and Entry delays - together with a timed Bell Cut-off and Reset. The basic alarm has a single zone. This will... [more]
August 4, 2010
This transistor based alarm features automatic Exit and Entry delays - together with a timed Bell Cut-off and system Reset. Along with the Exit/Entry zone - the basic alarm board has one Instant Zone. This... [more]
August 4, 2010
The circuit features automatic Exit and Entry delays, timed Bell Cut-off and System Reset. It has provision for normally-open and normally-closed switches and will suit the usual input devices (Pressure Mats, Magnetic Reed contacts, Foil... [more]
August 4, 2010
This circuit features automatic Exit/Entry delays, timed Bell Cut-off and System Reset. It has provision for normally-open and normally-closed switches and will accommodate the usual input devices (Pressure Mats, Magnetic Reed contacts, Foil Tape, PIRs... [more]
August 4, 2010
This circuit features automatic Exit/Entry delays, timed Bell Cut-off and System Reset. It will accommodate the usual normally-closed input devices (Magnetic Reed contacts, Micro Switches, Foil Tape and PIRs). And - with a simple modification... [more]
August 4, 2010
This is a single zone alarm - with automatic exit, entry and siren cut-off timers. It will accommodate all the usual types of normally-closed input devices - such as magnetic reed contacts, foil tape, PIRs... [more]
August 4, 2010
This is a selection of small self-contained alarm circuits. They have a very low standby current; and are suitable for battery operation. Some are triggered by normally-open and normally-closed switches. Some react to changes in... [more]
August 4, 2010
This is a selection of simple self-contained transistor based alarm circuits - complete with photographs. They are designed around the Complementary Latch. All may be triggered by both normally-open and normally-closed switches. They have a... [more]
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